1. Field of the Invention
This invention relates to a toner cartridge used for a copying machine.
2. Description of the Prior Art
A toner cartridge is very convenient as a toner feeding device because boner can be automatically fed to a developing tray by simply loading the toner cartridge containing the toner into a copying machine. As one representative example of such a toner cartridge, there is known a toner cartridge comprising a cylindrical cartridge body having a toner discharge port which is formed in a part of its peripheral surface along its longitudinal direction, a pivot shaft disposed at the axis of the cartridge body, and a toner pressure feeding member joined to the cartridge body through a plurality of connecting rods and adapted to discharge the toner contained in the cartridge body from the toner discharge port (Japanese Utility Model Early Laid-open Publication No. Sho 61-157962).
As toner has a very high fluidity, toner contained in a body of such a toner cartridge as mentioned above is moved to the toner discharge port as the toner is consumed and then discharged from the toner discharge port. However, toner which is in a position remote from the toner discharge port tends to remain in the body when the quantity of toner contained in the body becomes scarce.
In order to overcome the above mentioned shortcoming, there is proposed another toner cartridge as disclosed in Japanese Utility Model Early Laid-open Publication No. Sho 61-157962, which comprises a spiral scraping plate as a toner pressure feeding device so that toner, which tends to remain in the body, can be effectively transferred to the discharge port.
However, the above mentioned conventional toner cartridge has a such a problem that it is necessary to provide a space between the side edge of the scraping plate and the inner wall of the body in order to prevent a friction resistance from being generated therebetween and, as a result, provision of the spiral scraping plate is not sufficient for discharging all of the toner, some of which tends to remain in the body, into the discharge port. There is also another problem inherent in the above mentioned conventional toner cartridge, that is that much labor is required coupled with the necessity for making the space small in particular as mentioned.